Pinpoint Test F: DTC C1742 - Rear Sounder Circuit Failure And DTC C1743 - Rear Sounder Circuit Short To VBATT

WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

F1 USE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCs) FROM THE PARKING AID MODULE SELF-TEST
- Use the recorded results from the parking aid module self-test.
- Is DTC C1742 or C1743 recorded?
Yes : GO to F2.

No : All other DTCs, GO to the PARKING AID MODULE DIAGNOSTIC TROUBLE CODE (DTC) INDEX .

If no DTCs are recorded, GO to PINPOINT TEST B .
F2 MEASURE THE PARKING AID SPEAKER RESISTANCE
- Key in OFF position.
- Disconnect: Parking Aid Speaker C4015.
- Measure the resistance between the parking aid speaker pin 1, component side and the parking aid speaker pin 2, component side.
  
  Fig 1: Measuring Parking AID Speaker Resistance
  Courtesy of FORD MOTOR CO.
- Is the resistance between 40 and 60 ohms?
Yes : If DTC C1742 was recorded, GO to F3.

If DTC C1743 was recorded, GO to F7.

No : INSTALL a new parking aid speaker. REFER to PARKING AID MODULE . CLEAR the DTCs. REPEAT the self-test.
F3 CHECK CIRCUIT 1437 (BK/PK) FOR A SHORT TO GROUND
- Connect: Parking Aid Speaker C4015.
- Disconnect: Parking Aid Module C4014.
- Measure the resistance between the parking aid module, C4014-2, circuit 1437 (BK/PK), harness side and ground.
  
  Fig 2: Checking Circuit 1437 (BK/PK) For A Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
Yes : GO to F5.

No : GO to F4.
F4 CHECK CIRCUIT 1437 (BK/PK) FOR A SHORT TO GROUND WITH THE PARKING AID SPEAKER DISCONNECTED
- Disconnect: Parking Aid Speaker C4015.
- Measure the resistance between the parking aid module, C4014-2, circuit 1437 (BK/PK), harness side and ground.
  
  Fig 3: Checking Circuit 1437 (BK/PK) For A Short To Ground With Parking AID Speaker Disconnected
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
Yes : REPAIR circuit 1438 (DG). CLEAR the DTCs. REPEAT the self-test.

No : REPAIR circuit 1437 (BK/PK). CLEAR the DTCs. REPEAT the self-test.
F5 CHECK CIRCUIT 1437 (BK/PK) FOR AN OPEN
- Disconnect: Parking Aid Speaker C4015.
- Measure the resistance between the parking aid speaker C4015-2, circuit 1437 (BK/PK), harness side and the parking aid module C4014-2, circuit 1437 (BK/PK), harness side.
  
  Fig 4: Checking Circuit 1437 (BK/PK) For An Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
Yes : GO to F6.

No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
F6 CHECK CIRCUIT 1438 (DG) FOR AN OPEN
- Measure the resistance between the parking aid speaker C4015-1, circuit 1438 (DG), harness side and the parking aid module C4014-6, circuit 1438 (DG), harness side.
  
  Fig 5: Checking Circuit 1438 (DG) For An Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
Yes : GO to F8.

No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
F7 CHECK CIRCUITS 1437 (BK/PK) AND 1438 (DG) FOR A SHORT TO VOLTAGE
- Disconnect: Parking Aid Module C4014.
- Key in ON position.
- Measure the voltage between the parking aid module, C4014-2, circuit 1437 (BK/PK), harness side and ground; and between the parking aid module, C4014-6, circuit 1438 (DG), harness side and ground.
  
  Fig 6: Checking Circuits 1437 (BK/PK) And 1438 (DG) For A Short To Voltage
  Courtesy of FORD MOTOR CO.
- Is any voltage present?
Yes : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.

No : GO to F8.
F8 CHECK FOR CORRECT PARKING AID MODULE OPERATION
- Disconnect the parking aid module connector.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect the parking aid module connector and make sure it seats correctly.
- Operate the system and determine if the concern is still present.
- Is the concern still present?
Yes : INSTALL a new parking aid module. REFER to PARKING AID MODULE . TEST the system for normal operation.

No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.